Conventionally, as shown in FIG. 9, the present applicant has already proposed a component mounting apparatus in which its component mounting work area 2200 is divided into a front-side component mounting work area 2201 and a rear-side component mounting work area 2202 viewed from an operator. Each of the areas is provided with component feeding devices 2008A, 2008B, 2018A and 2018B and component recognition devices 2009 and 2019, and a front-side board conveying and holding device 2003 and a rear-side board conveying and holding device 2013 which can be laterally joined together are provided at a center of the component mounting work area 2200, in which arrangement when the front-side board conveying and holding device 2003 and the rear-side board conveying and holding device 2013 are joined together at the center, two boards 2002 and 2002 are loaded and held by the front-side board conveying and holding device 2003 and the rear-side board conveying and holding device 2013, respectively, and thereafter the front-side board conveying and holding device 2003 is moved to the front-side component mounting work area 2201 to perform component mounting, and the rear-side board conveying and holding device 2013 is moved to the rear-side component mounting work area 2202 to perform component mounting.
However, with the above structure, board 2002 can be loaded and unloaded only when the front-side board conveying and holding device 2003 and the rear-side board conveying and holding device 2013 are joined together at the center. Therefore, if component mounting is stopped due to some errors during the component mounting in, for example, the rear-side component mounting work area 2202, then the board 2002 cannot be unloaded when so tried unless the board is made to pass through the rear-side board conveying and holding device 2013 even though component mounting has ended in the front-side component mounting work area 2201. Therefore, if unloading of a component-mounted board, i.e. a completed product of which the component mounting has ended, is stopped for a long term, solder of the component-mounted board would be deteriorated, which may lead to a degraded mounting quality. Moreover, when mounting process time for performing component mounting of boards of different models differs between the front-side component mounting work area and the rear-side component mounting work area, or when the mounting process time differs due to a suction error or a recognition error during component mounting in, for example, the rear-side component mounting work area even in a case of mounting of identical boards and components. If a component-mounted board of which a component mounting has previously ended is made to stand by for a long period, then solder of the component-mounted board would be deteriorated, which may lead to a degraded mounting quality, as in the above case.
Accordingly, an object of the present invention is to solve the aforementioned problems and provide a component mounting apparatus and method by which, in concurrently performing component mounting operations in a plurality of component mounting work areas, respectively, if either component mounting has ended in advance, a board that has undergone the component mounting can be unloaded without awaiting termination of the other mounting operation or board unloading, thereby allowing areal productivity to be further improved, as well as a component mounting system equipped with a plurality of such component mounting apparatuses.